More than 2,000 children in all were separated from their parents by USA immigration authorities at the border this spring before President Donald Trump reversed course on June 20 amid an global outcry and said families should remain together.

"Their children are stranded in this country", the ACLU said of the children of deported parents.

In fact, through DNA testing, two adults who apparently thought they were parents of a child were determined not to be, he said.

Since the government first came under pressure to ease its policy on separations weeks ago, it has shifted its estimates of the number of children it would reunite.

The operation of facilities, like the one at Tornillo, "is a necessary and prudent step to ensure that the Border Patrol can continue its vital national security mission to prevent illegal migration, trafficking, and protect the borders of the United States", said Darcie Johnston, Director at the office of Intergovernmental Affairs at the Department of Health and Human Services, in a letter to Texas State Sen.

Wendy Young, president of the child advocacy group Kids in Need of Defense, said doing that would be "family separation part 2". On June 27, she finally made contact with her children and has been given weekly visitation rights. "Those were the worst days of my life". Levy said that one mother of a four-year-old was told by federal authorities to find a larger apartment if she wanted her son back.

Lugging little backpacks, smiling immigrant children were scooped up into their parents' arms Tuesday as the Trump administration scrambled to meet a court-ordered deadline to reunite dozens of youngsters forcibly separated from their families at the border.

U.S. President Donald Trump took to Twitter on Wednesday to blame the Democratic Party, among others, for not fixing immigration.

US District Judge Dolly Gee said the government had failed to present new evidence to support revising a court order that limits the detention of children who crossed the border illegally. Many of those who had left the country without their child, they claimed, had done so because leaving the child in the United States had been their intended goal. One parent was from Honduras and the other from El Salvador.

"Our clients still have not been reunified!" said Beth Krause, an attorney with Legal Aid Society's Immigrant Youth Project, in an email to Reuters.

For the remaining children, he said in about half of the cases, the government was still trying to finalize background checks and confirm parentage.

One of them might be a child of a USA citizen, the Justice Department acknowledged Tuesday when it notified a federal judge about the progress being made to complete more than 100 reunions. They could potentially argue that the USA government violated their constitutional rights.

The ACLU says they will not be seeking sanctions for the government not meeting the deadline, telling ABC News in a statement, "At this point, we think the most constructive way forward is that the Court continue to stay hands-on and keep the government moving forward".